1. Technical Field
The present disclosure relates to circuit architectures and communication methods thereof, and more particularly, multi-chip stack structures and signal transmission methods thereof.
2. Description of Related Art
Since the invention of the integrated circuit, the semiconductor industry has experienced continued rapid growth due to continuous improvements in the integration density of various electronic components (i.e., transistors, diodes, resistors, capacitors, etc.). For the most part, this improvement in integration density has come from repeated reductions in minimum feature size, which allows more components to be integrated into a given area.
These integration improvements are essentially two-dimensional (2D) in nature, in that the volume occupied by the integrated components is essentially on the surface of the semiconductor wafer. Although dramatic improvements in lithography have resulted in considerable improvement in 2D integrated circuit formation, there are physical limits to the density that can be achieved in two dimensions. One of these limits is the minimum size needed to make these components. Also, when more devices are put into one chip, more complex designs are required.
An additional limit comes from the significant increase in the number and length of interconnections between devices as the number of devices increases. When the number and length of interconnections increase, both circuit RC delay and power consumption increase.
In an attempt to further increase circuit density, three-dimensional (3D) integrated circuits (ICs) have been investigated. In a typical formation process of a 3D IC, two chips are bonded together, so as to avoid using a long transmission distance in a single large-area chip. In the 3D IC, signals are transmitted between two chips through silicon via; however, in this way, added processes of IC chip manufacturing and more masks must be required.
In view of the foregoing, there is an urgent need in the related field to provide a way to transmit signals between chips efficiently.